Wireless communication systems include Radio Base Stations (RBSs) that communicatively link wireless devices, such as cellular telephones, to a network system. Recently, a collaboration between multiple wireless providers produced the Common Public Radio Interface (CPRI) standard. The architecture for the CPRI standard separates the radio and controlling elements of an RBS by placing all control elements of the RBS in a Radio Equipment Controller (REC), and placing all radio elements in a Radio Equipment (RE) unit. The CPRI standard also defines an interface between the RE and REC. This architecture enables flexible and efficient product differentiation for RBSs and independent technology evolution for the RE and REC. Further, the CPRI architecture enables the REC and the RE to be remotely located from each other.
Because the RE is usually co-located with the antenna in the field, the size of the RE is commercially important, particularly for Long Term Evolution (LTE) and Wideband Code Division Multiple Access (WCDMA) systems. The size of the cooling fins required for cooling the radio elements primarily drives the size of the RE. Thus, minimizing the size and/or number of the cooling fins significantly reduces the size of the RE. The amount of power dissipation and operating temperature of the radio elements in the RE, along with the ambient temperature range of the environment surrounding the RE drive the size and/or number of the cooling fins.
To help control the size and/or number of the cooling fins, and therefore the RE, a conventional RE may include a self-protection mechanism that prevents the power dissipation of the RE from exceeding a predetermined maximum. The self-protection mechanism decreases the power output by the RE when the temperature reaches a predefined threshold. Such self-protection mechanisms decrease the power of all transmissions on the common, dedicated, and shared channels from the RE. However, decreasing the power of transmissions on the common channel decreases the cell radius of the RBS, which may result in dropped calls, limited coverage, etc.